the fact of other bodies, the earth, the heaven, or something else of the same kind interposing, between them and us. Besides, we must compare the different modes of explanation appropriate to phænomena, and recollect that it is not impossible that many causes may at one and the same time concur in their production.
(He says the same thing in the twelfth book of his treatise on Nature; and adds that the eclipses of the sun arise from the fact that it penetrates into the shade of the moon, to quit it again presently; and the eclipses of the moon from the fact of its entering into the shade of the earth. We also find the same doctrine asserted by Diogenes, the Epicurean, in the first book of his Select Opinions.)
“The regular and periodical march of these phænomena has nothing in it that ought to surprise us, if we only attend to the analogous facts which take place under our eyes. Above all things let us beware of making the Deity interpose here, for that being we ought to suppose exempt from all occupation and perfectly happy; otherwise we shall be only giving vain explanations of the heavenly phænomena, as has happened already to a crowd of authors. Not being able to recognize what is really possible, they have fallen into vain theories, in supposing that for all phænomena there was but one single mode of production, and in rejecting all other explanations which are founded on probability; they have adopted the most unreasonable opinions, for want of placing in the front the study of the heavenly phænomena, and of sensible facts, which ought to serve to explain the first.
“The differences in the length of nights and days may arise from the fact that the passage of the sun above the earth is more or less rapid; and more or less slow, according to the length of the regions which it has to pass through. Or, again, to the fact that certain regions are passed through more rapidly than